KVM: x86 emulator: Add into, int, and int3 instructions (opcodes 0xcc-0xce) (6e154e56) · Commits · 戴 / test

arch/x86/kvm/emulate.c

+78 −0

Original line number	Diff line number	Diff line
		@@ -1180,6 +1180,67 @@ static int emulate_popa(struct x86_emulate_ctxt *ctxt,
		return rc;
		}

		int emulate_int_real(struct x86_emulate_ctxt *ctxt,
		struct x86_emulate_ops *ops, int irq)
		{
		struct decode_cache *c = &ctxt->decode;
		int rc = X86EMUL_CONTINUE;
		struct desc_ptr dt;
		gva_t cs_addr;
		gva_t eip_addr;
		u16 cs, eip;
		u32 err;

		/* TODO: Add limit checks */
		c->src.val = ctxt->eflags;
		emulate_push(ctxt, ops);

		ctxt->eflags &= ~(EFLG_IF \| EFLG_TF \| EFLG_AC);

		c->src.val = ops->get_segment_selector(VCPU_SREG_CS, ctxt->vcpu);
		emulate_push(ctxt, ops);

		c->src.val = c->eip;
		emulate_push(ctxt, ops);

		ops->get_idt(&dt, ctxt->vcpu);

		eip_addr = dt.address + (irq << 2);
		cs_addr = dt.address + (irq << 2) + 2;

		rc = ops->read_std(cs_addr, &cs, 2, ctxt->vcpu, &err);
		if (rc != X86EMUL_CONTINUE)
		return rc;

		rc = ops->read_std(eip_addr, &eip, 2, ctxt->vcpu, &err);
		if (rc != X86EMUL_CONTINUE)
		return rc;

		rc = load_segment_descriptor(ctxt, ops, cs, VCPU_SREG_CS);
		if (rc != X86EMUL_CONTINUE)
		return rc;

		c->eip = eip;

		return rc;
		}

		static int emulate_int(struct x86_emulate_ctxt *ctxt,
		struct x86_emulate_ops *ops, int irq)
		{
		switch(ctxt->mode) {
		case X86EMUL_MODE_REAL:
		return emulate_int_real(ctxt, ops, irq);
		case X86EMUL_MODE_VM86:
		case X86EMUL_MODE_PROT16:
		case X86EMUL_MODE_PROT32:
		case X86EMUL_MODE_PROT64:
		default:
		/* Protected mode interrupts unimplemented yet */
		return X86EMUL_UNHANDLEABLE;
		}
		}

		static int emulate_iret_real(struct x86_emulate_ctxt *ctxt,
		struct x86_emulate_ops *ops)
		{
		@@ -2616,6 +2677,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
		struct decode_cache *c = &ctxt->decode;
		int rc = X86EMUL_CONTINUE;
		int saved_dst_type = c->dst.type;
		int irq; /* Used for int 3, int, and into */

		ctxt->decode.mem_read.pos = 0;

		@@ -2960,6 +3022,22 @@ special_insn:
		if (rc != X86EMUL_CONTINUE)
		goto done;
		break;
		case 0xcc: /* int3 */
		irq = 3;
		goto do_interrupt;
		case 0xcd: /* int n */
		irq = c->src.val;
		do_interrupt:
		rc = emulate_int(ctxt, ops, irq);
		if (rc != X86EMUL_CONTINUE)
		goto done;
		break;
		case 0xce: /* into */
		if (ctxt->eflags & EFLG_OF) {
		irq = 4;
		goto do_interrupt;
		}
		break;
		case 0xcf: /* iret */
		rc = emulate_iret(ctxt, ops);

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